Study On Long-term Peak-shaving Dispatch Model Of Cascade Reservoir Consider Short-term Peak-shaving Characteristic

The rapid economic and social development has brought a rapid increase in energy demand.Under the new situation of energy development in our country,a large number of new energy grids with randomness have a great impact on the safety and stability of the power grid system.The problem of the lack of peak power remains to be solved,and hydropower peak regulation will still be the main power grid peak regulation mode.In addition,in the field of hydropower peak regulation,the problem of link up between long-term peak regulation dispatching and short-term peak regulation dispatching has always existed.The problem that reflect short-term peak shaving operation characteristics in long-term peak shaving operation,the problem of the research is still relatively small.Therefore,this paper takes the Three Gorge cascade hydropower station as the research object,and studies the long-term peak regulation scheduling problem of cascaded hydropower stations with short-term peak coupling characteristics.The main contents and conclusions are as follows:(1)Summary of Research on Reservoir Regulation and Hydropower Peaking.Summarizes the current research status of the current reservoir dispatch and hydropower peak regulation at home and abroad,and further elaborates the status quo of the research on the peak-shaving regulation of the Three Gorges cascade hydropower station,and puts forward the existing problems and shortcomings.Based on this,this paper presents the research significance,research content and technical route.(2)Research on typical daily peak mode extraction of cascaded hydropower Stations.The daily peak mode reflects the daily peak-shaving operation characteristics of hydropower stations.In the monthly extraction period,synchronous back-reduction method in scene reduction method,and K-means clustering analysis method in cluster analysis method were used to extract the typical peak-daily mode of typical peak-daily mode set of the Three Gorges and Gezhouba hydropower stations.The maximum peak output,the minimum peak output and the peak-valley difference of the Three Gorges and Gezhouba hydropower stations are calculated as typical peak-shaving characteristics.(3)Research on economic benefit model of peak-shaving regulation in cascade hydropower stations.Taking the Three Gorges cascade hydropower station as the research object and based on the characteristics of the typical daily mode,the relationship between the peak price and the hours of peak-load utilization is constructed by the peak price curve,and compare two typical daily mode extraction modes of the peaking power price series.Establish a model with the goal of maximizing peak benefit,the dynamic programming method is used for solving the model.The comparative analysis of scheduling results shows that the optimal scheduling model based on typical daily peak mode can reflect the characteristics of short-term peak shaving characteristics during the scheduling period and increase the peak shaving efficiency to a great extent under the premise of not significantly reducing the generating capacity,mobilize the enthusiasm of the hydropower station to participate in peak regulation at the same time.(4)Research on efficiency model of peak regulation capacity of cascade hydropower stations.Taking the Three Gorges cascade hydropower station as the research object and considering the model building principle of peak-expected efficiency model,the maximum peak-regulating output power distribution pattern of Three Gorges and Gezhouba Hydropower Station was statistically analyzed.The distribution form and parameter values of the probability density function were determined.Two kinds of extraction methods were used to determine the maximum peak-limiting output series,the paper finally proposed cascade hydropower scheduling model based on binomial distribution,and with the uniform distribution of the scheduling results were compared.The results show that the binomial-based cascaded hydropower station peak-shaving expectation model takes better account of the actual operation characteristics of the hydropower station,reserves the peak-regulating capacity for the peak-load dispatching at the peak output stage of the hydropower station,and provides a new idea for leaving the peak capacity in the long-term regulation considers the short-term characteristics.